Sulu (Philippines) - Suspected Abu Sayyaf gunmen abducted four workers in a school in a southern Philippine province where President Rodrigo Duterte visited troops waging an offensive against the militants, officials said Sunday. About 20 militants barged into a grade school compound in Sulu province's Patikul town shortly after midnight Saturday and seized six painters and carpenters, one of whom managed to escape and alerted the police. Army troops later rescued another worker. Duterte pinned medals on wounded troops during brief visit Saturday to Sulu, a predominantly Muslim province about 950 kilometers south of Manila. The tough-talking president has ordered government forces to destroy the ransom-seeking militants who still hold several foreign and Filipino hostages in Sulu's jungles. Abu Sayyaf is a Jihadist militant group based in and around Jolo and Basilan islands in the southwestern part of the Philippines. Troops, backed by airstrikes, are fighting less than 100 remaining militants, who are holding an unspecified number of civilian hostages in four Marawi neighborhoods in an offensive that Duterte said last week was winding down and may end in about 10 to 15 days. He said that the offensive won't stop until the last militant is killed.